Copy machine paper control circuit

ABSTRACT

A length of copy paper is automatically drawn by a feed roll from a supply roll precisely measured and cut therefrom for merger with an original to be copied, by an integrated high-speed electronic control system in which movement of the original past an edge-sensor by a constant-speed motor starts the paper feed by closure of a feedroll clutch to the motor and the release of a feedroll brake, which feed continues at constant speed until the sensor initiates stoppage thereof by the application of the brake, opening of the clutch, and the paper cutting action of a knife, so that the so-cut length of copy paper corresponds substantially precisely to that of the original prior to subsequent copying of the original. A solid-state control circuit employing three storage capacitors and two commutating capacitors, is used to operate the three main elements of the system with such precise timing accuracy that a maximum variation of + OR - 1/64 inch in length is obtained with a paper feed speed of 5 to 60 feet per minute.

United States Patent Unangst [.4 1 Jan. 25, 1972 [54] COPY MACHINE PAPERCONTROL Primary ExaminerWilliam S. Lawson CIRCUIT Attorney-George L.Tone, Walter G. Hensel and Martin Smolowitz [72] Inventor: Richard E.Unangst, Binghamton, NY. [73] Assignee: GAF Corporation, New York, NY.[57] ABSTRACT A length of copy a er is automaticall drawn b a feed roll[22] Flled July 1969 from a supply roll pfecisely measured and cuttlierefrom for [21] A l N 838,416 merger with an original to be copied,by an integrated highspeed electronic control system in which movementof the original past an edge-sensor by a constant-speed motor starts[52] US. Cl ..83/203, 355/13 the paper feed by closure on feedro" clutchto he mmol. and [51] IIIL Cl. ..G03g 15/00 the release f a feedro brakewhich feed continues a com [58] Field of surch 204; 355/13 stant speeduntil the sensor initiates stoppage thereof by the 355/29 application ofthe brake, opening of the clutch, and the paper cuttin action of aknife, so that the so-cut len th of co [56] References Cited papercorresponds substantially precisely to t hat of the UNITED STATESPATENTS original prior to subsequent copying of the original. Asolidstate control clrcuit employing three storage capacitors and2,873,657 2/ 1959 Bartlett et al. ..83/203 UX two commutatingcapacitors, is used to operate the three main 3,182,539 5/ l 965Williams, Jr. ..83/203 UX elements of the system with such precisetiming accuracy that 3,292,471 12/1966 Sames et a1... ..83/203 21maximum variation of: H64 inch in length is obtained with 3,398,6198/1968 Nichols et al. ...83/203 UX a paper feed speed of 5 to 60 feetper minute. 3,452,627 7/1969 Goodman et al.. ..83/205 X 3,467,469 9/1969Hastings et al .355/13 x 8 Chin, 3 Figures PATENIEU Jmzsmz 3,636,307

sum 1 OF 3 INVENTOR. RICHFIAD E, ur/m/ssf BY Mflnfiu I smote win COPYMACHINE PAPER CONTROL CIRCUIT This invention relates to copy machines ofthe Diazo and electrostatic types, and more particularly to theautomatic copy paper handling subsystems thereof.

BACKGROUND It has been proposed in a companion application of Edwin D.Foulks, to have the forward movement of an original in a copy machineresult in the automatic withdrawal of a length of copy paper from asupply roll, which is cut to correspond to that of the original prior tothe copying action in which the original and the so-cut length of copypaper are merged. Thus, originals of varying length are provided withcorresponding lengths of copy paper.

SUMMARY OF INVENTION The present invention provides a simple, yetefficient, fast and accurate electronic control circuit for operatingthe clutch, brake and knife in precisely timed sequence to perfect theoperation of the proposed system, as outlined below.

A light-sensitive circuit energized by a voltage-regulated power supply,transmits a signal when the leading edge of an original. is moved past asensor by a conveyor driven by a running drive motor, as indicated by aREADY light that is connected to an AC source by a relay switch. Suchsignal operates a solid-state switch (SCM) which thereupon connects aclutch-solenoid to a first DC power supply and a storage capacitor inparallel therewith, to discharge the capacitor through the solenoidwhich closes a clutch to connect the so-running motor to a copy paperfeed roll.

At substantially the same instant a brake on the feed roll is releasedby a brake-solenoid as deenergization of the latter is speeded by acommutator-capacitor connected across common signal input terminals ofsuch solenoids. The copy paper and original are driven at a preselectedspeed by the motor until such signal is terminated by thelight-sensitive circuit in response to movement of the original past thesensor.

In the meantime, upon closure of the clutch by the discharge of itscapacitor, the latter also causes energization of the coil of the relayswitch which then disconnects the READY light from the AC source, andconnects such AC source to a second DC power source which thereuponcharges a knife-solenoid capacitor in parallel therewith.

When the sensor signal terminates, individual solidstate switchescontrolling the brake and knife-solenoid trigger the discharge of theircapacitors therethrough, applying the brake and operating the knife, asa commutation-capacitor connecting the signal-input circuits of theclutchand knife-solenoid speeds up deenergization of theclutch-solenoid. As a result the knife cuts a length from such copypaper that corresponds to that of the original.

The invention has proved to be capable of providing lengths of copypaper that correspond to lengths of the originals with a maximumvariation of :1 l l 6 inch at a constant paper-speed of between to 60feet/minute.

THE DRAWINGS FIG. 1 is a diagram of a paper control system embodying theinvention.

FIG. 2 is a block diagram of the control circuit therefor.

FIG. 3 is a circuit diagram of the invention.

GENERAL SYSTEM (FIG. 1)

A constant speed motor the speed of which is adjustable, drives aconveyor 12 which carries an original (master) 14 to be copied throughthe machine past an edge sensor 16. The leading edge of the original 14causes the sensor to transmit a signal which activates solenoid circuitsl8 and 20 to release a brake 22 from feed roll. 24 and close a clutch 26connecting the already running motor 10 to feed roll 24. The feed rollthereupon draws a strip of copy paper 28 from a supply roll 30 thereofand feeds such strip toward a cutting station 32 through a guide 34. Therunning of motor 10 is indicated by a READY light 36 being ON" beforeeach original is fed to the machine.

The motor 10 drives the original 14. and the copy paper 28 forwardly atthe selected speed until the trailing edge of the original 14 activatesthe sensor 18, whereupon the paper feed is stopped by the energizationof brake-solenoid circuit 18 and the opening of clutch 26 and theoperation of knife 38 by the energization of its solenoid circuit 40 tosever a length 42 of copy paper from the supply strip 28 thatcorresponds substantially exactly to that of the original 14. The mergedcopy and original are subsequently carried forwardly in mergedrelationship by a conveyor 44 which also is driven by the common drivemotor 10, to a copying station (not shown). The main elements of themachine are reset after each cutting operation, for handling asubsequent original and a corresponding length 42 of copy papertherefor.

CONTROL CIRCUIT (FIG. 2)

Isolation transformer 50 is connected to an AC supply line 52 andprovides power to the input of rectifiers 54, 56 and 58. While the inputof the rectifier 56 is connected directly to the secondary oftransformer 50, the input of the rectifier 52 is connected theretothrough relay (switch) contactors 60 when therclay coil (not shown)thereof in circuit 62 is energized which also disconnects the circuit ofREADY light 36 from the transformer 50. The rectifiers 54 and 56constitute first and second DC power sources for storage capacitors 64and 66, respectively, associated with the clutch-solenoid circuit 62 andknife-solenoid circuit 70. The rectifier 58 constitutes the third DCpower supply. The voltage of the latter is closely regulated for use inthe sensor and solid-state device circuits.

The DC power supply 58 furnishes power to photocell lamp 72 as well asto sensing network 74 of the photocell l6. Signal 76 of the leading edgeof an original is transmitted to SCR gate amplifier circuit 78 which inturn goes to SCR No.2 circuit 80 which operates clutch 80 which operatesclutch-solenoid circuit 62. The latter operatesbrake-solenoid circuit 82through a commutation (switching) capacitor 78.

The trailing edge of the original results in a signal 84 beingtransmitted to the inputs of SCR gate amplifiers 86 and 88, which inturn operate SCR No. 4 and No. 6 circuits 90 and 92, respectively. Thelatter operate the brakeand knife-solenoids 82 and 70; the latterspeeding up the release of clutch by virtue of commutation capacitor 94connected between circuits 62 and 70. The clutch-solenoid 62, thebrake-solenoid 82 and the knife-solenoid 70 are provided with currentstorage capacitors 64, 96 and 66, respectively; the discharge of whichspeeds up the energization of the corresponding solenoids when triggeredby the corresponding SCR transistors.

As shown in FIG. 2, the photocell 74 and the lamp 72 are arranged sothat the leading edge of the master paper (original) provides signal 76for the clutch gate amplifier 78, energizing the clutch and relay RY]coil, and also turning oh the brakesolenoid82 through C1 capacitor 78.The trailing edge of the master paper provides signal 84 for the brakegate amplifier 86, thus energizing the brake-solenoid. This same gatesignal also turns on the knifewsolenoid gate amplifier 88, energizingthe knife-solenoid 70 and turning off the clutch-solenoid and relay RYIcoil circuit 62 through C2 capacitor 94.

CIRCUIT DIAGRAM (FIG. 3)

The electronic control circuit includes the solar cell 16 on which therays of the light source 72 are directed. The edgesensing circuitnetwork 74 is connected to the regulated DC power supply 58, and isprovided with an adjustable resistor respectively. The SCR relays inturn, control the magnetic clutch-solenoid 62, the magneticbrake-solenoid 82 and the knife-solenoid 70. The latter are providedwith parallel resistance-rectifier (diode) circuits 110, 114 and 116, toassure unidirectional reverse-current flow in each.

Power supply 54 consists of a bridge-type rectifier, the DC outputnegative terminal of which is grounded by lead 18. The positive side ofsuch output is connected by lead 120, to the center of resistor R3, theouter terminals of which are connected to the ungrounded terminals ofthe clutchand brakesolenoids 62 and 82, respectively. The latter areprovided with the current storage capacitors 64 and 96, as well as thecommutating capacitor 78.

Similarly, the knife-solenoid is provided with the current storagecapacitor 66, and is connected to the clutch relay 80 by the commutationcapacitor 94. The positive side of rectifier bridge 56 is connected tothe knife-solenoid 70 by lead 122 containing rectifier diode 124 andresistor 126, the negative side of the rectifier 56 being grounded at128. Ready light 36 is normally connected to stationary contacts 128,128 are connected to the secondary 130 of the isolation transformer 50,the primary 132 of which is connected to the AC power line 52. Thus,when relay coil 134 is energized, movable switch contacts 136, 136 leavecontacts 128, 128, deenergizing ready light 36; and engage stationarycontacts 138, 138, energizing the AC input of the bridge 56.

The electronic control circuit operates the three solenoid elements(clutch, brake and knife) in precisely timed sequence whereby one (thefirst) that is normally off is closed when the corresponding solenoid isenergized, a second that is normally on is released by deenergization ofthe corresponding solenoid upon such energization of the first solenoidand a third that is normally off, is subsequently energized to close andthereby simultaneously deenergizes the first solenoid thus, restoringthe corresponding first element to such normally off position.

The resistor R1 provides means for adjusting the response time of thesolenoids.

CONCLUSION The invention provides an electronic control circuit forcontrolling the feeding and cutting of copy paper drawn from a supplyroll in response to movement of an original by a constant-speed motorpast an edge-sensor prior to merger of the original and the length ofso-cut copy paper for the copying operation, in which the copy paperdrive is connected to such motor by a normally open clutch, a normallyapplied brake stops such drive, and a knife is normally poised out ofthe way of the copy paper to be cut thereby, and individual solenoidsare provided for closing said clutch, releasing said brake, andoperating said knife when energized.

The control circuit involves:

l. An individual current storage capacitor for discharging an energizingcurrent through the corresponding solenoid when triggered to do so.

2. Individual DC supply circuits for charging said capacitors when thecorresponding solenoids are deenergized, there being afirst DC supplycircuit for said clutchand brake-solenoid current storage capacitors,and a second DC supply circuit for said brake-solenoid current-storagecapacitor.

3. A relay having a coil connected in parallel with saidclutch-solenoid, and normally open contactors for connecting said secondDC supply circuit to a common AC source when said coil is energized.

4. A READY light normally connected to such AC source by said relaycontactors.

5. Individual solid-state devices acting when fired to trigger thedischarge of said capacitors through their corresponding solenoids.

6. Commutatmg capacitors connected between said clutchandbrake-solenoids, and between said knifeand brake-solenoids for speedingup the restoration of the corresponding elements by facilitating thedeenergization of said brakeand clutch-solenoids when the clutchandknife-solenoids respectively, are energized first to start the copypaper feed and then subsequently to stop and cut the copy paper,respectively.

7. A circuit for applying a leading-edge signal from such original-edgesensor to said clutch solid-state device when the leading edges of anoriginal is moved by the motor past the sensor, as well as atrailing-edge signal to said knife solid-state device when the trailingedge of such original subsequently moves past the sensor.

I claim:

1. In a copy machine in which a lengthof copy material (paper) is drawnfrom a supply roll and cut in response to movement of a master(original) past an edge sensor by a common drive motor so that'suchlength corresponds to that of the master;

an electronic control circuit for operating a clutch connecting saidmotor to a copy paper feed roll, a brake for said roll, and a knife forcutting the copy paper in precisely timed sequence, comprising:

individual capacitor discharge-energized solenoids associated with saidclutch, brake and knife, respectively;

one DC power supply source connected to charge said clutch and brakecapacitors while the clutch and brake are idle;

another DC power source for energizing said knife capacitor only whilesaid clutch is closed;

individual solid-state devices for switching the correspondingcapacitors in discharge connection with their corresponding solenoids inresponse to a signal from the edge sensor;

a signal circuit for first transmitting a master leading edge signal tosaid clutch solid-state device, and then a trailing edge signalsimultaneously to said brake and knife solidstate devices. I g

2. The invention as defined by claim 1, in which the sensor comprises atransistorized photocell circuit provided with a resistor that isadjustable.

3. The invention as defined by claim 2, in which the photocell circuitis connected to a closely regulated voltage DC source of supply otherthan that of the other two DC power supply sources.

4. The invention as defined by claim 1, in which the clutch and brakesolenoids are connected by one commutating capacitor, and the knife andclutch solenoids are connected by another commutating capacitor.

5. The invention as defined by claim 1, in which the second DC powersupply is a bridge-type rectifier, the input of which is connected to anAC source only when the clutch-solenoid is energized by a relay having acoil connected in parallel with said solenoid and contactors which closeto make such connection when the coil is energized.

6. The invention as defined by claim 1, in which said relay contactorsnormally connect a READY light to such AC source, but disconnect thelatter when the relay coil is energized.

7. The invention as defined by claim 6, in which said solidstate devicesare SCR transistors.

8. The invention as defined by claim 7, in which SCR transistors arecontrolled by SCR gate amplifiers.

1. In a copy machine in which a length of copy material (paper) is drawnfrom a supply roll and cut in response to movement of a master(original) past an edge sensor by a common drive motor so that suchlength corresponds to that of the master; an electronic control circuitfor operating a clutch connecting said motor to a copy paper feed roll,a brake for said roll, and a knife for cutting the copy paper inprecisely timed sequence, comprising: individual capacitordischarge-energized solenoids associated with said clutch, brake andknife, respectively; one DC power supply source connected to charge saidclutch and brake capacitors while the clutch and brake are idle; anotherDC power source for energizing said knife capacitor only while saidclutch is closed; individual solid-state devices for switching thecorresponding capacitors in discharge connection with theircorresponding solenoids in response to a signal from the edge sensor; asignal circuit for first transmitting a master leading edge signal tosaid clutch solid-state device, and then a trailing edge signalsimultaneously to said brake and knife solid-state devices.
 2. Theinvention as defined by claim 1, in which the sensor comprises atransistorized photocell circuit provided with a resistor that isadjustable.
 3. The invention as defined by claim 2, in which thephotocell circuit is connected to a closely regulated voltage DC sourceof supply other than that of the other two DC power supply sources. 4.The invention as defined by claim 1, in which the clutch and brakesolenoids are connected by one commutating capacitor, and the knife andclutch solenoids are connected by another commutating capacitor.
 5. Theinvention as defined by claim 1, in which the second DC power supply isa bridge-type rectifier, the input of which is connected to an AC sourceonly when the clutch-solenoid is energized by a relay having a coilconnected in parallel with said solenoid and contactors which close tomake such connection when the coil is energized.
 6. The invention asdefined by claim 1, in which said relay contactors normally connect aREADY light to such AC source, but disconnect the latter when the relaycoil is energized.
 7. The invention as defined by claim 6, in which saidsolid-state devices are SCR transistors.
 8. The invention as defined byclaim 7, in which SCR transistors are controlled by SCR gate amplifiers.